Materials Data on Ba2Ti4Cr2O13 by Materials Project
Ba2Ti4Cr2O13 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ba2+ is bonded in a 11-coordinate geometry to eleven O2- atoms. There are a spread of Ba–O bond distances ranging from 2.72–3.26 Å. There are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share a cornercorner with one CrO6 octahedra, corners with three equivalent TiO6 octahedra, an edgeedge with one TiO6 octahedra, and edges with two equivalent CrO6 octahedra. The corner-sharing octahedra tilt angles range from 0–15°. There are a spread of Ti–O bond distances ranging from 1.80–2.27 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form distorted TiO6 octahedra that share corners with two equivalent TiO6 octahedra, edges with three TiO6 octahedra, and edges with three equivalent CrO6 octahedra. The corner-sharing octahedral tilt angles are 30°. There are a spread of Ti–O bond distances ranging from 1.78–2.24 Å. Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share a cornercorner with one TiO6 octahedra, corners with two equivalent CrO6 octahedra, and edges with five TiO6 octahedra. The corner-sharing octahedra tilt angles range from 12–18°. There are a spread of Cr–O bond distances ranging from 1.99–2.07 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded to three equivalent Ti4+ and one Cr3+ atom to form a mixture of distorted edge and corner-sharing OTi3Cr trigonal pyramids. In the second O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Ba2+, one Ti4+, and one Cr3+ atom. In the third O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ba2+, one Ti4+, and one Cr3+ atom. In the fourth O2- site, O2- is bonded in a distorted T-shaped geometry to two equivalent Ba2+, two equivalent Ti4+, and one Cr3+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+ and two Ti4+ atoms. In the sixth O2- site, O2- is bonded in a linear geometry to four equivalent Ba2+ and two equivalent Ti4+ atoms. In the seventh O2- site, O2- is bonded to one Ba2+, two Ti4+, and two equivalent Cr3+ atoms to form a mixture of distorted edge and corner-sharing OBaTi2Cr2 trigonal pyramids.